VANCOUVER ISLAND MARMOT (Marmota vancouverensis)
The Vancouver Island marmot is a locally common, endemic resident in the mountains of southeastern Vancouver Island. The species is RED-listed, and designated as ENDANGERED by COSEWIC and under the British Columbia Wildlife Act.
Reasons for this designation include small population size and concentrated range. The Vancouver Island marmot is one of the rarest mammals in North America, with a stable or declining population of 200-300 animals. Approximately 75% of the known population occurs in a core area of subalpine habitat of less than 2000 hectares, however prehistoric evidence and historic records indicate that the species formerly occupied a more extensive range. A recovery plan has been written by the Canadian Vancouver Island Marmot Recovery Team, under the auspices of the Committee on the Recovery of Nationally Endangered Wildlife.
The Vancouver Island marmot is herbivorous and an obligate hibernator. It occupies high elevation clearings and talus slopes, which provide lush grass and herbs for foraging, and cavities and ground-burrow habitat adequate for denning and escaping predators. The elevation of natural marmot colonies varies from 1040 m to 1450 m. Colonies in logged areas are at a lower elevation (800 m to 1000 m). The Vancouver Island marmot is slow to achieve sexual maturity and exhibits low reproductive rates. Litter sizes of 1 to 5 are produced, but most females do not breed until age four, and in most cases there is a non-reproductive interval of at least one year between litters. Relatively few females survive long enough to produce more than one litter. The major causes of mortality appear to be predation (cougar, wolf, large raptors) and unsuccessful hibernation.
The range is very restricted. Most marmot colonies occur in south-central Vancouver Island at the headwaters of the adjacent drainages of the Nanaimo, Chemainus, Nitinat, Cameron and Cowichan Rivers. One small isolated colony also occurs on Mt. Washington in east-central Vancouver Island.
MH: MHmm1, MHmmp1
Site series (preliminary approximation)
a) Mountain hemlock - Amabilis fir - Mountain-heather in the MHmm and MHmmp subzones.
b) Amabilis fir - Mountain hemlock - Twistedstalk in the MHmm and MHmmp subzones.
c) Douglas-fir - Western Hemlock - Salal in the CWHmm subzones.
AH, AM, AU, AV, FR, HP, MF, SM, TA
The best marmot habitat occurs in natural subalpine meadows that have pockets of deep soil for hibernacula and burrows. Adjacent rock faces are also important as a source of boulders and rocky ledges for loafing and look-out sites. This basic structure can also be approximated in some clear-cuts, where road-cuts provide sites for hibernacula and burrows, and stumps and coarse woody debris provide loafing and look-out sites.
Lush herbaceous plant communities are required as foraging habitat. The Vancouver Island marmot feeds primarily on grass-like plants in spring (oatgrass, sedges, woodrush), and forbs in the summer (lupines, peavince, paintbrush, meadowrue, cow parsnip, wooly sunflower). In natural habitats, the Anaphalis-Aster wildflower community provides both a diversity of food resources and soil conditions suitable for burrowing. Early-seral plant communities that occur after logging can also provide foraging areas for marmots.
In natural marmot habitat, snow creep and avalanches are believed to be responsible for maintaining the treeless conditions required for social contact and detection of predators. At lower elevations, the early-seral stages preferred by marmots can be created by fire or clear-cut logging, but the survival of marmots in these clear-cut habitats may be considerably less than that in natural marmot habitat. This topic is currently under investigation.
The Vancouver Island marmot generally prefers steep areas between 35 and 90% slope. Aspects from south to west are preferred because of early spring snowmelt.
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